A containership owner is suing a US pharmacist for its role in supplying a series of medical drugs to a San Francisco maritime pilot who was found to be guilty of causing the Cosco Busan to collide with the San Francisco-Oakland Bay Bridge, which tore a huge gash in the side of the vessel and resulted in 53,000 gallons of bunker fuel being spilled into local waters.

The vessel’s pilot, John Cota, a member of the San Francisco Bar Pilots Association for 26 years, pleaded guilty to federal pollution and spent 10 months in prison.

Hong Kong-based owner Regal Stone Ltd, along with the vessel’s technical manager Fleet Management Ltd, filed the suit in the San Francisco Superior Court this week, alleging that Longs Pharmacy should also be held responsible for the incident, which took place in November 2007, because it had been supplying Cota with a cocktail of prescription drugs since 2004 for a variety of medical conditions he had, which ultimately impaired his cognitive ability to the extent that it directly caused the accident.

Indeed, the degree to which Cota’s judgement was impaired is jaw-dropping, accroding to the account of the incident in the deposited papers. On the morning of the collision, San Francisco’s notorious fog had reduced visibility to just a quarter of a mile, while local safety guidelines recommended that vessels should not traverse the deepwater channels if visibility is below half a mile.

However, Cota decided that the vessel’s radar system and electronic charts would be adequate to navigate safely, despite the fact that all other pilots working that morning had cancelled their voyages. Once the Cosco Busan had departed, events took an even stranger turn, according to the papers:

“Cota later claimed that after departing the dock, he lost confidence in the radar he was using, because he claimed the radar image had become distorted. Cota instead decided to navigate using the ship’s electronic chart… Subsequent examination of the radars by investigative authorities confirmed that the radars were functioning normally.

“Even though the electronic chart used standard nautical symbols for the buoys in front of the bridge towers, Cota became disorientated and confused as the vessel proceeded. As the vessel approached the bridge, Coat asked the ship’s master (who was Chinese) what the triangles on the chart adjacent to the bridge towers represented. The master was surprised that the pilot was asking him such a basic navigational question, and responded that they were “on bridge”. Cota misinterpreted this to mean that the symbols marked the centre of the span. It is hard to conceive how an experienced pilot could have needed help understanding what a standard chart symbol meant. A fair analogy would be a commercial taxi driver asking his passenger what a stop sign means.”

Not only that, but he also forgot to release a stern line that connected to vessel to a tug, which meant the 5,500teu containership was effectively towing its tug through San Francisco Bay. Indeed, it was only when the coast guard’s vessel traffic services called Cota to confirm that he intended to pass under the bridge’s Delta-Echo span that he realised he was aiming directly for the bridge’s Delta tower. In panic, he issued a series of confused orders, some of which countermanded each other and the vessel side-swiped the tower.

There was massive local public outrage over the incident, due to both the size of the spill and the slow reporting of the incident – although it took place in the morning the local authorities weren’t informed of its full extent until the evening – and in the resulting court cases the two Hong Kong companies were ordered to pay $44.4m in compensation to the clean-up authorities and a further $3.6m to local fishermen.

However, they are now attempting to recoup those, as well as lost earnings and other costs from Longs Pharmacy, who they claim was negligent in not informing the coast guard or his pilot association of his prescription use, or even advising him not to operate heavy machinery while he was using the medication.

One crucial event in the investigation of the incident was an email sent by an unnamed employee of Longs to the US Coast Guard, which said simply: “Check John Cota for prescription drugs. I can’t say more than that.”

Odd to think that if the suit is upheld, then a humble pharmacy will have been found to be responsible for one of the most serious environmental disasters involving a containership in recent times.